Mercedes Sprinter 2.2 CDI - High Pressure Pump - Two different pumps

Daro122 wrote:

and what is the section cut off for?

Below I paste a drawing showing the principle of operation high pressure regulating valve (zrwc) (1) and switch off section of the 3rd piston (9) in the high pressure pump BOSCH CP1 .

It should be noted that pwc with the switch off section of the 3rd piston is very obsolete and used in 1st generation injection systems BOSCH up to the year more or less 2003.

The section is just a simple electromagnetic valve, designed to disable (as the name suggests) one of the plungers from the fuel pump. The valve operates in 2-state mode via a current pulse supplied by the control computer. So it is either "on" if the computer provides power. Pwc then works on two pistons, i.e. it has reduced efficiency by 1/3. And "off" if the computer does not power electrically. Pwc works with full 100% performance.

Of course, the action does not consist in stopping one piston completely, but on maintenance low pressure fuel input valve (green color) in the "open" position. Then the piston moves with the rotation of the pump drive shaft, but does not compress the fuel to high pressure (red), and only "have" fuel in the low pressure area.

Removal of this valve and non-blinding of the input valve will cause the fuel to pee outside during operation.

Why do you need this valve? It fulfills the role of additional regulation of fuel pressure in the tank in relation to zrwc (1), which is the main regulating valve. If there is a need to quickly vent fuel into the tank, for example in the event of a fire, this valve helps zrwc by switching off the 3rd plunger, as mentioned above.

As you can see, he does not have too much work, unlike zrwc, who must work without interruption while driving. It is mainly due to the breakdown of zrwc that the engine stops working, capriciousness, jerks, etc., and not because of the section of the 3rd piston.

I mentioned previously that it is an outdated system. Currently in all engines Common Rail in the world ranging from popular passenger cars, BMW, Audi, French, Japanese, Korean, and ending with large, 12-cylinder, vane ship monsters - it is used Expense regulator whose principle of operation is discussed in more detail eg. in the subject https://www.elektroda.pl/rtvforum/topic3301938.html.

Pzdr KotBury2